In SituMeasurement of Sintering Shrinkage in Powder Compacts by Digital Image Correlation Method

Abstract

AbstractAn In Situ system for monitoring sintering shrinkage of powder compacts using digital image correlation has been developed. This system will provide completely automated non-contact measurement of two dimensional deformation, and thus enables In Situ quantification of non-uniform and anisotropic shrinkage, if any, of a powder compact during sintering. A brief description is given of the procedure for identifying micro-areas on a specimen surface before and after deformation by the digital image correlation method. A new digital image processing algorithm has been developed to determine the two-dimensional distribution of shrinkage rate in powder compacts during sintering. A measurement of the shrinkage non-uniformity in a die pressed carbonyl nickel powder compact during sintering from room temperature to 1573 K is presented. The results showed successful identification of non-uniform and anisotropic shrinkage arising from powder filling inhomogeneities and the neutral zone effect of die wall fric...